Something I read in one of Gary Drayton's books on the Minelab Sovy-Excal a few days ago sparked a memory of a basic discipline, or understanding of detector tune/sensitivity and it's relationship to coil ground coverage, or more specifically, target inclusion. In the race for more depth, we (I) tend to tweek up as much sensitivity as possible, often running the ragged edge of stability (false iron signals) which the Etrac is famous for.
I took this newly remembered concept for a ride over some ground at my local courthouse lawn. Now if I have done this once, I have done it 30 times over the past 20 years. I have many silvers, in cards with dates to remind me just how productive this little site has been. After so much thorough gridding, from many different angles, production started slowing down. Well, I de-tuned the Etrac to auto -3 and within 15 minutes popped 3 wheats, 3 to 5 inches from ground I can prove I have covered with several machines, including the Etrac for the past 2 years.
Apparently, the decreased sens s the "knife-shaped" cone (DD coil) to make it thinner, hence a thinner detect zone in which to include the iron. Seems to give alot of the benefits of putting on a smaller coil, only faster and cheaper. Oh, did I mention this is "nail-heaven"? Rusty, square, iron ones at that!
Some may balk at the idea of "turning down the heat" on the Etrac, claiming it will see right through iron. But let's be honest, even the Etrac, mighty as it may be, is still just a processor, managing input/output. It's not the fastest machine on the planet, but it is awesome, even more so if we don't overload it with extra iron to sort through.
So, this is just another tool in the kit for us to use on a given site if you are haunted by the ghosts of nails past. Hit 'er in auto plus or high manual as usual, then come back over in auto minus 3...you may just be surprised! HH

I have done this with all my detectors. I actually run a manual on 10. Seems to be the golden zone for my etrac. I am new to the etrac and only have a few hours on it. I plan to get it dirty this upcoming year for sure. I have seen how good a etrac can pull the old coppers and silvers here. It takes a lot of discipline to start off low and go high sens. But I agree detuning the etrac will produce.

People always want to know where to hunt. I like old newspaper clippings and the library of congress my self.